// detects when the other transform is closer than closeDistance
// this is faster than using Vector3.magnitude

var other : Transform;
var closeDistance = 5.0;

function Update() {
if (other) {
var sqrLen = (other.position - transform.position).sqrMagnitude;
// square the distance we compare with
if( sqrLen < closeDistance*closeDistance )
print ("The other transform is close to me!");
}
}

using UnityEngine;
using System.Collections;

public class example : MonoBehaviour {
public Transform other;
public float closeDistance = 5.0F;
void Update() {
if (other) {
float sqrLen = other.position - transform.position.sqrMagnitude;
if (sqrLen < closeDistance * closeDistance)
print("The other transform is close to me!");

}
}
}

import UnityEngine
import System.Collections

class example(MonoBehaviour):

public other as Transform

public closeDistance as single = 5.0F

def Update():
if other:
sqrLen as single = (other.position - transform.position).sqrMagnitude
if sqrLen < (closeDistance * closeDistance):
print('The other transform is close to me!')